Basic battery questions from a beginner

[Alaska59]

Hello, I just bought my first RV, a 2008 Dodge Sprinter 2500, with a 2009 Winnebago ERA top. Here are a couple of basic questions I have about the rig.
Why would Mercedes/Dodge put the main chassis battery in an inaccessible place under the driver's seat, while leaving an auxiliary battery place empty under the hood? That doesn't make sense to me. What if I need to jump the main chassis battery? I have to remove the driver's seat? Since the vehicle I just bought is 12 years old, it would make sense to replace the batteries now, or at a minimum add the auxiliary battery under the hood so I can get a jump if I ever need it. Please advise. The previous owner kept this rig on two Battery Tender smart chargers over the winter. Is that a reasonable way to manage this?

 

[OrioN]

Hello, I just bought my first RV, a 2008 Dodge Sprinter 2500, with a 2009 Winnebago ERA top. Here are a couple of basic questions I have about the rig.
Why would Mercedes/Dodge put the main chassis battery in an inaccessible place under the driver's seat, while leaving an auxiliary battery place empty under the hood? That doesn't make sense to me. What if I need to jump the main chassis battery? I have to remove the driver's seat? Since the vehicle I just bought is 12 years old, it would make sense to replace the batteries now, or at a minimum add the auxiliary battery under the hood so I can get a jump if I ever need it. Please advise. The previous owner kept this rig on two Battery Tender smart chargers over the winter. Is that a reasonable way to manage this?

There are jumper posts under the hood. If you have the vehicle manual, it would help you identify the locations. If not, do a search here for the many pictures....

 

[Winterbagoal]

Suggest you download and read the OM for the 2009 ERA. It tells you how to use the "battery boost switch", and if that doesn't work, how to use the information in the 2008 Sprinter chassis manual to connect and boost from an external power source, like another vehicle battery. No need to pull the cockpit apart.
No idea on the condition of your batteries, but if it ain't broke, don't fix it. I'd charge them up by taking the rig for a longish spin, let them rest for a few hours, and then test them with a multi-meter. Remove any loads if possible, before testing them, or, if they test OK as is, then you'd be good to go.
OK, how did the previous owner connect the Battery Tenders? Always hot 12V outlets? I use a Stanley 8A charger/maintainer plugged into an inverter fed 110V AC outlet, and the other end into the always hot 12VDC outlet under the ashtray on the dash to maintain my chassis battery from the coach batteries. The coach batteries get charged by shore power (plugged in) or by the 300W of solar up top. It works well, so if your seller did it that way, it must work, no? Others will recommend adding a Trik-L-Start or an Amp-L-Start battery connector to connect the chassis/coach batteries via the isolator solenoid under the passenger seat, but that was more trouble then I was willing to tackle, so I went with my method.

 

[Alphacarina]

Some sort of 1 or 2 amp regulated trickle charger (not from Harbor Freight) will extend the life of most any battery, so that's a good idea

I would load test all your batteries, especially if you don't know how old they are. I think the folks at AutoZone have load testers and will do it for free, on the off chance that they can sell you a new battery. I *do* believe in replacing batteries before they leave me stranded beside the road . . . . in a strange place . . . . . at night . . . . . in the rain/sleet/snow. One such episode is more than worth the price of a new battery, no matter what it costs

Don

 

[autostaretx]

A Sprinter 2008 owner's manual is here: http://www.diysprinter.co.uk/reference/2008_Sprinter_Owners_Manual.pdf

And "full" 2007 service info is here:
http://www.diysprinter.co.uk/reference/2007-sprinter-service-information.pdf <-2007 MB service manual
http://www.diysprinter.co.uk/reference/2007-sprinter-wiring-information.pdf <- MB wiring diagram from above
http://www.diysprinter.co.uk/reference/2007_Wiring-sprinter-2500.pdf <-- 3rd party wiring diagrams


--dick

 

[maasthor]

you can charge the chassis battery using the red positive post under the hood and the grounding post on the side; both in the engine compartment. they are directly connected to the battery, so no need to open the floor up to get at the battery. some people use the lower 12V cigarette lighter to trickle charge.

 

[Alaska59]

Thank you, everybody! All of this is very helpful. I do have the ERA operator manual for 2009 and the Sprinter Chassis manual for 2008. I haven't made it all the way through the latter, but I have read the former a couple of times and it sometimes isn't very clear. For example, on page 5-3, in the section called "Safe use of the propane gas system," it says, "Turn the propane supply valve off when not using the propane gas system."
Hmm. So, you should certainly close the supply valve when you're storing the vehicle. I get that. What about when you're driving from one campsite to the next? Should you turn it off then? What about when you go to sleep at night?

 

[Cheyenne]

Hello, I just bought my first RV, a 2008 Dodge Sprinter 2500...

Why would Mercedes/Dodge put the main chassis battery in an inaccessible place under the driver's seat...

Unless Winnebago moved the chassis battery then it will not be under the drivers seat but under the floor IN FRONT of the drivers seat!

Are you sure it is the chassis battery under the drivers seat and not a second auxiliary battery?

Keith.

 

[TJLee089]

Storage - definitely turn LP off
Driving - Frig should run on 12v DC powered by the alternator; LP can be off, but not necessary
Overnight - If camped without AC power, LP must be on to run the fridge

Thank you, everybody! All of this is very helpful. I do have the ERA operator manual for 2009 and the Sprinter Chassis manual for 2008. I haven't made it all the way through the latter, but I have read the former a couple of times and it sometimes isn't very clear. For example, on page 5-3, in the section called "Safe use of the propane gas system," it says, "Turn the propane supply valve off when not using the propane gas system."
Hmm. So, you should certainly close the supply valve when you're storing the vehicle. I get that. What about when you're driving from one campsite to the next? Should you turn it off then? What about when you go to sleep at night?

 

[Alphacarina]

Driving - Frig should run on 12v DC powered by the alternator; LP can be off, but not necessary

There are places it's required to be shut off - Tunnels, ferries and such. I'd be very careful at gas stations if it's left on too

Don